
; create an empty vector of length 4 and
; a fill pointer of 2
; and is adjustable (allowed to grow)
(setf v (make-array 4 :fill-pointer 2 :adjustable t))

(print v)

; use the fill-pointer to add "3" to index 2
(vector-push 2 v)

(print v)

; set the fill-pointer to 0, effectively
; making it of length 0
(setf (fill-pointer v) 0)

(print v)

; add one to vector
(vector-push 1 v)

(print v)

; the rest of the "inactive" list has not been
; deleted and is still accessible by index
(print (aref v 2))